Building security systems are becoming increasingly more important. Many buildings have sign-in stations, security guards, machine readable security credentials, smart turnstiles that manage the count of people entering and leaving a building, video surveillance, and more.
Businesses disposed in buildings would prefer that only people who are entitled to be on the floors that they inhabit be populated with people who have permission to be there. Moreover, many high rises have elevators which open directly into residences or secured areas.